Bring 250 ml water, salt and butter to the boil in a saucepan. Add flour while stirring. Stir until the dough separates from the bottom of the pot as a lump and a thin skin forms on the bottom
Put the dough into a mixing bowl and quickly stir in 1 egg with the dough hooks of the hand mixer. Let dough rest for about 12 minutes. Then stir in 4 eggs one after the other. Stir in baking powder. Put the dough on a greased baking tray and spread evenly. Leave an approx. 1 cm wide rim free. Bake in a preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: see manufacturer) for approx. 20 minutes. Let the tray cool down on a cake rack
In the meantime, caramelise sugar in a pan for the pudding. Dissolve the espresso powder in 250 ml boiling water. Add the caramelized sugar while stirring. Bring to the boil and simmer over a low to medium heat for about 10 minutes
Cut the choux pastry in half crosswise. Cut a pastry sheet into 12 pieces (approx. 5 x 10 cm). Pour cherries into a sieve and drain well. Pour 600 ml milk, cream and espresso syrup (makes approx. 150 ml) into a pot, bring to the boil. Stir starch and 75 ml milk until smooth. Pour into the boiling syrup-espresso milk and bring to the boil while stirring, let simmer for about 1 minute. Whisk the egg yolks, stir in 2-3 tbsp. of the pudding in very small quantities, then mix with the remaining pudding
Carefully fold the cherries into the pudding immediately. Spread evenly on a pastry sheet. (It must be worked very quickly, as the pudding sets quickly). Chill for about 15 minutes. Place the lid pieces close together and refrigerate again for about 30 minutes. Cut into predetermined pieces, dust with icing sugar and decorate with caramel threads as desired
waiting time approx. 2 hours